float llLog(float arg)

Returns the natural logarithm of the argument. The natural logarithm is a logarithm in base e (the Euler constant, which is approximately 2.7182818).

The float value whose natural logarithm is to be calculated.

Returns a float which is the natural logarithm of the argument.

• In order to make sense, the argument must be greater than 0.0; a value of 0.0 or less yields 0.0.
• The function returns Infinity if the input is Infinity, and 0.0 if the input is -Infinity or NaN.
• To calculate the logarithm in base 10, llLog10 can be used.
  • To calculate the logarithm in any other base, divide the result of this function by the logarithm of that base.
  • For example, to calculate the logarithm in base 2 of a number, use llLog(number)/llLog(2). Since the latter is constant, to save calculations and memory you can instead pre-calculate the reciprocal and multiply by it, like this: llLog(number)*1.44269504 will give you the logarithm in base 2, because 1/llLog(2) equals approx. 1.44269504.
• There is no built-in inverse of this function. To raise the Euler constant to a power, use llPow. But there is also no built-in definition for the Euler constant either, so you will need to use its value, which is approx. 2.7182818.

float f;
f = llLog(2.7182818); // sets f to 1 approx.
f = llLog(1);   // sets f to 0
f = llLog(2);   // sets f to 0.693147 approx.
f = llLog(0.5); // sets f to -0.693147 approx.
f = llLog(-1);  // sets f to 0
f = llLog(8)*1.44269504; // sets f to 3 approx.

• llLog10 to calculate the logarithm in base 10.
• llPow to raise a number to a power (also called antilogarithm).
• float type and associated caveats and limitations.